we would like to add a backup battery for the RTC clock for the Jetson Nano Devkit. According to
the J45 mark can be used for that purpose. However, on page 12 it states
An optional back up battery can be attached to the PMIC_BBAT module input. It is used to maintain the RTC voltage when VDD_IN is not present. This pin is connected directly to the onboard PMIC. When a backup cell is connected to the PMIC, the RTC will retain its contents and can be configured to charge the backup cell. The following backup cells may be attached to the PMIC_BBAT pin:
· Super Capacitor (gold cap, double layer electrolytic)
· Standard capacitors (tantalum)
· Rechargeable Lithium Manganese cells
The backup cells MUST provide a voltage in the range 2.5V to 3.5V. These will be charged with a constant current (CC), constant voltage (CV) charger that can be configured between 2.5V and 3.5V CV output and 50uA to 800uA CC.
We have the following questions:
Can we use a non-rechargeable CR1225/BR1225 cell battery like https://www.amazon.de/dp/B0042KHKCA ? So far we were unable to find a rechargeable CR1225/BR1225 cell battery.
Can we use power sources that supply 3.6 volts?
What are actual products that satisfies these properties? We would like to buy such.
What does "can be configured" in "charger that can be configured between 2.5V and 3.5V CV output and 50uA to 800uA CC" exactly mean? Is this done in software?
Best regards from Berlin!